Suri, D., Rahmawati, W. T. dan Lubis, S. I. (2024) “IMPROVING STUDENTS’ VOCABULARY MASTERY BY USING DUOLINGO OF THE EIGHTH GRADE AT SMPS BUDI UTOMO ”, Pedagogi: Jurnal Ilmiah Pendidikan, 10(1), hlm. 102–110. doi: 10.47662/pedagogi.v10i1.675.